The objective of the Animal Core is to provide investigators of the Program Project scientific, technical and financial support for the design and execution of their studies. The availability of a centralized state of the art facility is needed for the acquisition and housing of the Fischer 344 rats that will be utilized in the ischemia-reperfusion and antioxidant intervention studies, i.e. TNF expression in the aging and ischemia- reperfused heart damage to complex III, oxidative modification of the Rieske iron protein, cardiolipin status and free fatty acid oxidation and the thiol defense mechanism. In addition, the facility will be needed to conduct on-site short and longer term intervention studies in a pathogen- free environment and the development of a novel model of accelerated aging. The specific aims of this core are 1. To coordinate the acquisition and distribution of Fischer 344 rats and their tissues among Program Project investigators involved in ischemia-reperfusion studies, 2. To provide housing for Fischer 344 rats and other rodents involved in these studies under a centralized, specialized facility routinely monitored for compliance with standards of health applicable to gerontological studies (pathogen free environment, body weight measurement, physical and histological examination), 3. To provide assistance with scientific design and execution of protocols involving special diets and pharmacological treatments to study aging animals, and 4. To provide training for new investigators of the Program Project in the utilization of micro-isolators and special techniques pertinent to gerontological studies and studies involving pathogen-free animal stains. Services to the Investigators of the Program Project will be provided by a team consisting of the Core director (V. Monnier) assisted by 2 Co- directors, i.e. an expert in Animal Sciences and Barrier Facility for longevity studies with NIA rodents (DR. Sell, PhD) and a Veterinarian (N. Kleinman, DVM). A 50% FTE Research Assistant will assume the day-to-day operation of the facility in collaboration with the staff of the Animal Resources Center at CWRU. It is expected that this broadly designed Animal Core will allow us to integrate new projects of relevance to the Program Project while fulfilling its primary role.